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Java Java Objects Delivering the MVP Applying a Discount Code

Mike Zammit
Mike Zammit
1,813 Points

Trouble with Code Challenge: Applying a Discount Code

I'm trying to complete this code challenge, the first task completes fine, but the second keeps coming up and telling me that my first task doesn't run anymore. When I go back and click on the error, it's the exception the 2nd task has asked me to create.

See my code attached, but I've used the Character.toCharArray() method to convert the string into chars, and then used an if statement to check each using the .isLetter() method or != '$'. Am I doing something wrong here?

Order.java
public class Order {
  private String itemName;
  private int priceInCents;
  private String discountCode;

  public Order(String itemName, int priceInCents) {
    this.itemName = itemName;
    this.priceInCents = priceInCents;
  }

  private String normalizeDiscountCode(String discountCode) {
    for (char symbol : discountCode.toCharArray()) {
      if (! Character.isLetter(symbol) || symbol != '$') {
        throw new IllegalArgumentException("Invalid discount code");
      }
    }
    return discountCode.toUpperCase();
  }

  public String getItemName() {
    return itemName;
  }

  public int getPriceInCents() {
    return priceInCents;
  }

  public String getDiscountCode() {
    return discountCode;
  }

  public void applyDiscountCode(String discountCode) {
    this.discountCode = normalizeDiscountCode(discountCode);
  }

}
Example.java
public class Example {

  public static void main(String[] args) {
    // This is here just for example use cases.

    Order order = new Order(
            "Yoda PEZ Dispenser",
            600);

    // These are valid.  They are letters and the $ character only
    order.applyDiscountCode("abc");
    order.getDiscountCode(); // ABC

    order.applyDiscountCode("$ale");
    order.getDiscountCode(); // $ALE


    try {
      // This will throw an exception because it contains numbers
      order.applyDiscountCode("ABC123");
    } catch (IllegalArgumentException iae) {
      System.out.println(iae.getMessage());  // Prints "Invalid discount code"
    }
    try {
      // This will throw as well, because it contains a symbol.
      order.applyDiscountCode("w@w");
    }catch (IllegalArgumentException iae) {
      System.out.println(iae.getMessage());  // Prints "Invalid discount code"
    }

  }
}

1 Answer

Mike Zammit
Mike Zammit
1,813 Points

I've figured it out. In this section:

private String normalizeDiscountCode(String discountCode) { for (char symbol : discountCode.toCharArray()) { if (! Character.isLetter(symbol) || symbol != '$') { throw new IllegalArgumentException("Invalid discount code"); }

The if statement should be looking for &&, not ||